Analysis of the Effect of Abamectin Used in Plant Roots
In China, many vegetable growers reflect that abamectin has little effect on prevention meloidogyne, and some farmers even say there is no effect at all. However, studies have shown that abamectin has a strong repelling and killing efficacy on root-knot nematode, ectoparasites and other arthropods. Why do vegetable growers say it doesn’t work?
Through exchanges with some vegetable growers, Chinese researchers learned that the poor effect of avermectin was related to their use. Many vegetable growers felt that spraying avermectin to the roots very troublesome, so they just let avermectin flow with water into the ground, in order to control root-knot nematodes, which the effects must be greatly reduced in such a way, because avermectin need using 1500-2500 multiples times to ensure its effectiveness. That is, every cubic meter of water needs about one pound avermectin, for such a large amount, few farmers can make it. Once less than this concentration, it is difficult to give full play to the role of averment, which is the reason why the vegetable growers reflect the poor effect of avermectin control on root-knot nematode.
According to information that not only abamectin avermectin, but there are a lot of other pesticides (mostly used for spraying the roots), which farmers use to flush with water that actually, is just a waste of pesticides and the effect is not good as it is difficult to control the working concentration of pesticide by water flushing which is hard to control the water flow and to calculate how much pesticide should be filled, so farmers can only do the spraying in an approximate concentration range, once fail to reach the optimal concentration range, then the effect would be difficult to guarantee.
Furthermore, the cost of pesticide for spraying roots is quite high. For a time of moderate quantity watering, about 20 tons of water per acre, you need 40 kg pesticides if the effective concentration of the drug is 500 times; If it is 2000 times, you also need 10 kg pesticides, in this way the cost of buying pesticide becomes a big deal.
In addition, flushing pesticide with water increases the pesticide residues in soil. If the pesticide flushing is all year round, the excessive pesticide residues in soil will then break the balance of soil microorganism, the harm existing for a long time, and it is also difficult to estimate the potential problems.
In this regard, here is the reminder for vegetable growers from the researchers: When using pesticides, you must operate strictly according to the instructions, for instance, to prevent root knot nematode with avermectin, it is preferably to use monoclonal irrigating cooperating with chitin in the growing season spraying, using 1000-1500 times avermectin liquid, 250 ml per plant irrigation. This can ensure its concentration, and cause no waste.
Use 1.8% avermectin EC. In order to prevention root knot nematodes, you need full spray the soil surface evenly before planting with per square meter 1 to 1.5 ml potion, diluted into 2000-3000 times, then immediately rake into 15-20 cm of topsoil, seed or plant after fully mixed. According to the test and production application, it shows that 1.8% avermectin EC has an effect up to 65%~88% on root knot nematode disease control. But in some places, the defending efficiency decreased for years of continuous use. Other soil sterilization techniques should be matched with or used alternately. Besides, among not a few avermectin mixed pesticides on current market, the effective composition content (for preventing and controlling of root knot nematodes) of these mixed pesticides is very low, and the survey found that the abamectin insecticides some producers provide are of very poor efficiency.